I believe her history points to a number of interesting training ideas.
First some athletes maybe should look to move down instead of up. Distance focused coaches tend to look to adding distance and sometimes this could be a mistake.
Second each athlete is different and should be evaluated through testing in and out of track meets. As a coach I feel it is sound to have the athlete race events above and below their "best event" to figure out if there are opportunities in a different event.
Third many sprint coaches have bought into a training trend that is very minimalis in training load. I believe for 200, 400, and 800meter athletes need what many modern sprint coaches believe would be large loads of speed endurance work in their training history. Anecdotal evdience points to success comes from larger training loads.
Side note: Interesting article was written recently about a young rising sprint athlete got to train with Usain Bolts camp. In this article he was very surprised at the amount of volume the did in their sessions.
Look for my book to come out next fall titled The Sprinters Compendium.